thats what I tried. But when i press enter it changes Type to just Set and the dialog to set the Association is not available anymore,
When i try to select java.util.Set with the button you circeled on the screenshot, ivy doesnt ask for the type as it does when i select list. it just closes the dialog and then the type is Set (not Set<t>).

Ivy also shows an error that says:
The field type 'java.util.Set' does not support persistence.

are you able to choose the association type after?
when i tried, it only showed an association when i switch from list to set, but i cant change it.
e.g. there are no items to select from the dropdown (ONE_TO_ONE 7 ONE_TO_MANY)

when i want to give a new attribute the type set (full qualified name + generic type) the button to select the association doesnt even show.